Before you get set on this, can I suggest you look seriously at internet please.
Idk about Wales but in the countryside locations I would want to live in in N Yorkshire (about a dozen of them), we have been repeatedly hampered by unfeasible internet.
So I started a thread on here, and loads of people said 'don't be silly, it's fine, we have x, and we have y, and you can try this' So I went back to a bunch of locations people said were fine, found a new bunch of houses, and most of them were very far from fine.
Power cuts also have to be considered, though if you have 800k I guess you can afford a backup generator or something?
We are rural now. A tractor went into our phone line and we had no internet for 30 days. Luckily we have good mobile data and survived, can't say the same applies elsewhere - we had to order new Sims for a mast that is 300 ft away, so we got lucky there.
Ofc Starlink exists, but you have no way of knowing if it will work and how well until you are in the house with the kit.
Anyyyyyyyway, have a good look at it if it's crucial.
And if anyone in N Yorks wants to sell me their lovely countryside or village house with a great internet connection, hit me up! :p